The open, cargo section of a truck, such as the bed of a pickup, is typically used to haul cargo or store objects that do not fit in the limited cab space. One disadvantage of open bed designs is that objects placed in the cargo section are exposed to weather, vandalism, and theft. Conventional cover systems exist that protect the contents of the bed from weather and in some aspects from theft. However, a disadvantage of these conventional cover systems is that the area above the cover cannot be used to transport additional materials, such as plywood, wall-board, or other bulky items, without preventing access to the contents of the bed. Furthermore, many conventional covers have the added disadvantage of not being able to coexist with ladder racks, if the truck is so equipped.
For example, U.S. Pat. No. 6,254,169 provides a storage cover, but prevents access to materials on top of the box, allows no access from the sides to the interior of the truck bed when the cover is open, and cannot be readily used in conjunction with ladder racks. As with most conventional designs, the covers pivot vertically from the truck bed. When open, the bed covers are nearly perpendicular to the perimeter lip of the bed.
U.S. Pat. Nos. 5,299,722 and 6,234,559 describe cover assemblies with integrated toolboxes. These designs also do not allow for materials to be carried on the assembly and cannot easily be incorporated with a standard ladder rack. The designs allow for only limited access from the sides or rear to the interior of the truck bed. Again, the covers of these systems do not raise and lower in a parallel manner to the bed of the truck.
U.S. Pat. Nos. 4,522,440; 5,104,175; and 6,299,232 describe raising cover systems where the cover pivots up from the perimeter of the truck bed. The disclosed cover cannot be readily used in conjunction with ladder racks. Further, materials may not be transported on top of the cover. These designs allow for only limited access to the interior of the truck bed when the unit is raised.
U.S. Pat. No. 4,613,181 discloses a light duty cover that raises in a substantially parallel manner to the perimeter of the truck bed, but lacks a suitable storage box under the cover to provide security for tools and other materials. The disclosed system also lacks the ability to support loads on the cover or to lift them from the resting position. The ability to easily use the system with ladder racks also is lacking.
U.S. Pat. No. 4,328,989 describes a storage container that may be raised from the truck bed. While the design allows for materials to be transported on top of the container, the depicted apparatus does not readily allow for use with ladder racks and requires a complex system of shafts, chains, and sprockets to operate. Furthermore, the depicted apparatus prevents the use of the interior portion of the truck bed except for items held in the storage container and mounts the lifting posts to the bed of the truck. Such mounting of the lifting posts to the bed of the truck requires alteration of the truck bed with holes and the like.
As apparent from the above description, there is an ongoing need for a truck bed cover system that provides protection, security, and access to the contents of the bed, while simultaneously allowing for additional materials to be carried above the cover.